Room-temperature operation is often considered the holy grail of terahertz quantum cascade laser research, as it has proven quite difficult due to the destruction of population inversion by LO-phonon scattering between radiative subbands. One approach to higher temperature operation is by employing the "phonon bottleneck" effect, where lateral confinement is introduced to such a degree that LO-phonon scattering is rendered ineffective between radiative subbands due to the narrow LO linewidth. This work presents preliminary modeling work on the use of semiconductor nanowire axial heterostructures for this purpose, including calculations of bandstructure, optical transition rates, electromagnetic properties, and scattering rates. Additional experimental work supports the electromagnetic model. Final calculations suggest that semiconductor nanowires are indeed a worthy approach towards high-temperature operation in quantum cascade lasers and other intraband devices.

Semiconductor nanowires promise to provide the building blocks for a new generation of nanoscale electronic and optoelectronic devices. Semiconductor Nanowires: Materials, Synthesis, Characterization and Applications covers advanced materials for nanowires, the growth and synthesis of semiconductor nanowires—including methods such as solution growth, MOVPE, MBE, and self-organization. Characterizing the properties of semiconductor nanowires is covered in chapters describing studies using TEM, SPM, and Raman scattering. Applications of semiconductor nanowires are discussed in chapters focusing on solar cells, battery electrodes, sensors, optoelectronics and biology. Explores a selection of advanced materials for semiconductor nanowires Outlines key techniques for the property assessment and characterization of semiconductor nanowires Covers a broad range of applications across a number of fields

This book covers virtually all aspects of semiconductor nanowires, from growth to related applications, in detail. First, it addresses nanowires’ growth mechanism, one of the most important topics at the forefront of nanowire research. The focus then shifts to surface functionalization: nanowires have a high surface-to-volume ratio and thus are well-suited to surface modification, which effectively functionalizes them. The book also discusses the latest advances in the study of impurity doping, a crucial process in nanowires. In addition, considerable attention is paid to characterization techniques such as nanoscale and in situ methods, which are indispensable for understanding the novel properties of nanowires. Theoretical calculations are also essential to understanding nanowires’ characteristics, particularly those that derive directly from their special nature as one-dimensional nanoscale structures. In closing, the book considers future applications of nanowire structures in devices such as FETs and lasers.

GaN and ZnO nanowires can by grown using a wide variety of methods from physical vapor deposition to wet chemistry for optical devices. This book starts by presenting the similarities and differences between GaN and ZnO materials, as well as the assets and current limitations of nanowires for their use in optical devices, including feasibility and perspectives. It then focuses on the nucleation and growth mechanisms of ZnO and GaN nanowires, grown by various chemical and physical methods. Finally, it describes the formation of nanowire heterostructures applied to optical devices.

Semiconductor Nanowires: Part B, and Volume 94 in the Semiconductor and Semimetals series, focuses on semiconductor nanowires. Includes experts contributors who review the most important recent literature Contains a broad view, including examination of semiconductor nanowires

This book, the second of two volumes, describes heterostructures and optoelectronic devices made from GaN and ZnO nanowires. Over the last decade, the number of publications on GaN and ZnO nanowires has grown exponentially, in particular for their potential optical applications in LEDs, lasers, UV detectors or solar cells. So far, such applications are still in their infancy, which we analyze as being mostly due to a lack of understanding and control of the growth of nanowires and related heterostructures. Furthermore, dealing with two different but related semiconductors such as ZnO and GaN, but also with different chemical and physical synthesis methods, will bring valuable comparisons in order to gain a general approach for the growth of wide band gap nanowires applied to optical devices.

Semiconductor Nanowires: Part A, Number 93 in the Semiconductor and Semimetals series, focuses on semiconductor nanowires. Contains comments from leading contributors in the field semiconductor nanowires Provides reviews of the most important recent literature Presents a broad view, including an examination of semiconductor nanowires Comprises up to date advancements in the technological development of nanowire devices and systems, and is comprehensive enough to be used as a reference book on nanowires as well as a graduate student text book